"AirPods audio glitches until I adjust volume: My AirPods audio doesn’t play until I adjust the volume level? This is only a recent issue I’ve been having and I’ve restarted, updated, and repaired my devices, but to no avail."
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Report back if this works...
Increase the Headphone Volume Limit:
You can limit the maximum volume of sound that plays through headphones or the built-in speaker on your iPhone.
- Go: Settings app
- Tap: Sounds & Haptics
- Tap: Headphone Safety (first-item up from bottom of screen)
- Toggle On: Reduce Loud Audio
- Drag the Slider: to a higher decibel
Source: AirPods connected but no sound - Apple Community
Note: It is a 2017 post, but it might just do the job, having researched how to accommodate this in the most-recent iOS release: iOS27